JP2529754Y2 - Laminates for cold forming - Google Patents

Description

[Detailed description of the invention]

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a cold-formed laminate mainly for obtaining a cold-formed packaging material, and particularly to a cold-formed laminate suitable for obtaining a molded packaging material for pharmaceuticals, foodstuffs and the like. The present invention relates to a laminate for use.

[0002]

2. Description of the Related Art Conventionally, cold-formed packaging materials have been used as packaging materials for pharmaceuticals, foodstuffs and the like. And this packaging material is manufactured by cold-forming the laminated body which consists of an aluminum foil, a polyvinyl chloride resin sheet layer, and a sealant layer. The aluminum foil is present in the laminate in order to impart a desired tensile strength to the packaging material so that the packaging material is not easily broken. Further, the reason why the polyvinyl chloride resin sheet layer is present is to provide the packaging material with shape retention after cold forming. The reason for the presence of the sealant layer is to heat seal the lid or the container body after forming the packaging material, or to heat seal the packaging materials. In addition, as a material of the sealant layer, polyethylene or polypropylene is generally used.

[0003] However, the above-mentioned laminate has a drawback that delamination occurs during cold forming. Further, when the packaging material after cold forming and heat sealing is opened, the packaging material is torn, but at this time, the packaging material has a drawback that stringing and fluffing (feathering) occur. Was. These occur because the adhesive strength between the aluminum foil and the polyvinyl chloride resin sheet layer and the adhesive strength between the polyvinyl chloride resin sheet layer and the sealant layer are weak. In addition, since the polyvinyl chloride resin generally contains a plasticizer, the plasticizer evaporates from the polyvinyl chloride resin sheet layer when the packaging material after cold molding is heat-sealed, and the content is reduced. It also has the disadvantage of adversely affecting certain pharmaceuticals and foodstuffs.

[0004]

SUMMARY OF THE INVENTION Accordingly, the present invention is directed to a cold-formed laminate in which a specific polyester resin sheet layer is used in place of the polyvinyl chloride resin layer and the adhesive strength between the layers is increased. To prevent delamination at the time of cold forming or feathering at the time of opening the formed packaging material, and also have a bad influence upon heat sealing the packaging material. Is prevented from occurring.

[0005]

That is, the present invention relates to a method for producing an aluminum foil, a carboxylic acid-modified polyolefin resin layer, a urethane adhesive layer, an unstretched polyester resin sheet layer, a linear polyester resin and an inorganic resin from the surface. The present invention relates to a laminate for cold forming, which is laminated in the order of a mixed layer of powder and a lubricant.

Hereinafter, description will be made with reference to the drawings. FIG.
FIG. 3 is a cross-sectional view illustrating a laminated structure of the cold-formed laminate according to an example of the present invention.

In FIG. 1, reference numeral 3 denotes an aluminum foil. The thickness of the aluminum foil 3 is about 7 to 200 μm, preferably 30 to 200 μm.
About 70μ is good. The aluminum foil 3 is located on the surface of the cold forming laminate. Although not shown, a printing layer, a protective layer made of a synthetic resin film, an adhesive layer, and the like may be provided on the front side of the aluminum foil 3 as desired.

Reference numeral 4 denotes a carboxylic acid-modified polyolefin resin layer. The carboxylic acid-modified polyolefin-based resin is obtained by adding a carboxylic acid to a side chain of a polyolefin, and is generally obtained by adding maleic acid or maleic anhydride to a side chain. Specifically, Rioflex manufactured by Toyo Ink Manufacturing Co., Ltd., Unistor manufactured by Mitsui Petrochemical Industries, Ltd., and the like are used. In FIG. 1, the carboxylic acid-modified polyolefin-based resin layer 4 is composed of a laminate of an organosol coating 5 of a carboxylic acid-modified polyolefin-based resin and a carboxylic acid-modified polyolefin-based resin film 6.

Reference numeral 7 denotes a urethane-based adhesive layer. As the urethane-based adhesive, a conventionally known adhesive can be arbitrarily used.

Reference numeral 8 denotes an unstretched polyester resin film layer. The unstretched polyester resin film is formed by a conventionally known method, that is, extruding a molten polyester resin from a die to form a film, and thereafter, without strongly stretching. Therefore, the polyester polymer chain in the polyester-based resin film, compared with the case of uniaxially stretched or biaxially stretched polyester-based resin film,
Insufficient orientation is obtained, and the crystallinity is low.

Reference numeral 9 denotes a mixed layer of a linear polyester resin, an inorganic powder and a lubricant. The mixed layer 9 functions as a sealant layer of the packaging material during cold forming. The linear polyester resin is obtained by copolymerizing a dibasic acid represented by terephthalic acid, isophthalic acid, adipic acid and the like and a diol represented by ethylene glycol and propylene glycol and has a branch. No linear polyester resin. This linear polyester resin is flexible, has high adhesive strength when melted at a relatively low temperature, and has various excellent properties such as being harmless to the human body in terms of food hygiene and environmental hygiene. is there. As the inorganic powder, silicon dioxide, talc, kaolin, alumina or the like is used. As the lubricant, higher fatty acids or salts thereof are used. The linear polyester resin and the inorganic powder are bonded to each other with a desired adhesive strength (the mixed layer 9 and the mixed layer 9).
Is obtained, and an easy peeling property (easiness of peeling off the mixed layer 9 and the adherend to which the mixed layer 9 is bonded by heat sealing) is obtained. It is blended in an appropriate ratio. Specifically, the inorganic powder is 5 to 50 parts by weight based on 100 parts by weight of the linear polyester resin. If the amount of the inorganic powder is less than 5 parts by weight, a desired easy-peel property tends not to be obtained.
Conversely, if the amount of the inorganic powder exceeds 50 parts by weight, a desired adhesive strength tends to be hardly obtained. In addition, the lubricant is added to the total amount of the linear polyester resin and the inorganic powder in an amount of 0.
It is blended at a ratio of about 05 to 5% by weight. The amount of lubricant is 0.05
When the amount is less than the weight percentage, the slipperiness of the mixed layer 9 forming one surface of the mixed layer is deteriorated, and the tendency that cold forming is difficult is caused. Conversely, if it exceeds 5% by weight,
When this mixed layer 9 is made to function as a sealant, the amount of the lubricant evaporated at the time of heat sealing or the like increases, which may adversely affect the contents.

The above-described cold-formed laminate is pressed under pressure between a male mold and a female mold at room temperature to form a packaging material having a desired shape.

[0012]

The aluminum foil is for imparting a desired tensile strength to the cold-formed laminate, so that the laminate is not easily broken. Further, even when the packaging material is cold-formed into a packaging material, a desired tensile strength is provided so that the packaging material is not easily broken.

The carboxylic acid-modified polyolefin-based resin layer is for improving the adhesion between the aluminum foil and the urethane-based adhesive layer.

The urethane-based adhesive layer is for firmly bonding the unstretched polyester-based resin sheet layer to the carboxylic acid-modified polyolefin resin layer.

The unstretched polyester resin sheet layer is used in place of the conventional polyvinyl chloride resin sheet layer. That is, it is used to improve the shape retention of the cold-formed packaging material. In addition, this sheet layer is formed of an unstretched polyester resin in order to strongly adhere a mixed layer of a linear polyester resin serving as a sealant layer, an inorganic powder, and a lubricant to the urethane adhesive. belongs to. For example, when a uniaxially stretched or biaxially stretched polyester resin is used instead of the unstretched polyester resin, a mixed layer of a linear polyester resin, an inorganic powder, and a lubricant that functions as a sealant layer is uniaxially stretched or biaxially stretched. Does not firmly adhere to the stretched polyester resin sheet layer. The reason for this is that the polyester polymer chains of the uniaxially stretched or biaxially stretched polyester resin are highly crystallized, and thus, when a molten linear polyester is applied, it is difficult for each polyester polymer to be compatible with each other. It is estimated that Therefore, the mixed layer functioning as a sealant layer and the uniaxially stretched or biaxially stretched polyester resin sheet layer do not strongly adhere to each other, and when the laminate is cold-formed, delamination easily occurs and the packaging material is torn. Even in this case, feathering is likely to occur. In addition, since the unstretched polyester resin sheet has not been stretched yet, it exhibits high elongation and is excellent in moldability.

The mixed layer of the linear polyester resin, the inorganic powder and the lubricant functions as a sealant layer after cold forming. The linear polyester-based resin has the above-mentioned excellent properties, and is therefore suitable as a sealant for packaging materials. Further, the inorganic powder is for reducing the adhesive strength of the linear polyester-based resin to provide easy peelability after heat sealing. Further, the lubricant is intended to impart a slip property to the mixed layer forming one surface of the laminate, and to improve the slip property with the male mold or the female mold at the time of cold molding, so that cold molding is easy. That's what we do.

[0017]

As described above, the cold-formed laminate according to the present invention comprises an aluminum foil, a carboxylic acid-modified polyolefin-based resin layer, a urethane-based adhesive layer, an unstretched polyester-based resin sheet layer, and a linear laminate. Since it is laminated in the order of the mixed layer of the polyester resin, the inorganic powder, and the lubricant, the whole is firmly adhered. Therefore, this cold-formed laminate has an effect that it is difficult to peel between layers during cold-forming, and hardly causes delamination. Further, using a packaging material obtained by cold-forming this laminate, after sealing with a lid material or a container body, even if the packaging material is torn when opening this, it is difficult for the layers to peel off. Also, an effect that feathering is hardly generated can be obtained. Furthermore, the container obtained using this packaging material has a high adhesive strength between the layers of the packaging material, so that it is difficult for the layer to peel off during use and does not adversely affect the sealing property of the container or the appearance of the container. It also has an effect.

On one surface of the laminate for cold forming, there is a mixed layer of a linear polyester resin, an inorganic powder and a lubricant. Therefore, the slipping action of the lubricant in the mixed layer has an effect of being excellent in moldability during cold forming. Also,
When the mixed layer functions as a sealant layer after cold forming, a high adhesive force is obtained as a sealant by the action of the linear polyester resin and the inorganic powder of the mixed layer, and an easy peeling property with the adherend is obtained. It also has the effect of being excellent. Furthermore, in the laminate for cold forming according to the present invention, there is no polyvinyl chloride resin sheet layer, and thus no plasticizer contained in the polyvinyl chloride resin. Therefore, there is also an effect that the plasticizer can be prevented from evaporating at the time of heat sealing and adversely affecting the contents.

An unstretched polyester resin sheet layer is present in the laminate for cold forming in order to improve shape retention after forming. Since the unstretched polyester resin sheet has a high elongation, the deformation can be increased by deep drawing or the like, and the unstretched polyester resin sheet has an effect of being hardly broken during cold forming. In addition,
Although the case where the laminate according to the present invention is cold-formed as a packaging material has been mainly described above, the laminate for cold forming according to the present invention is also used for other uses such as interior materials such as wall materials. It is possible.

[Brief description of the drawings]

FIG. 1 is a cross-sectional view showing a laminated structure of a cold-formed laminate according to an example of the present invention.

[Explanation of symbols]

 3 Aluminum foil 4 Carboxylic acid-modified polyolefin resin layer 7 Urethane adhesive layer 8 Unstretched polyester resin sheet layer 9 Mixed layer

──────────────────────────────────────────────────続 き Continued on the front page (51) Int.Cl. ⁶ Identification code Agency reference number FI Technical display location B32B 27/36 B32B 27/36

Claims (1)

(57) [Scope of request for utility model registration] 1. An aluminum foil, a carboxylic acid-modified polyolefin-based resin layer, a urethane-based adhesive layer, an unstretched polyester-based resin sheet layer, and a mixed layer of a linear polyester-based resin, an inorganic powder, and a lubricant. A laminate for cold forming which is laminated.